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Sep 22, 2013
09/13

by
Wen-Cong Chen; Xiang-Dong Li

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Recent investigations on the delay time of type Ia supernovae have set useful constraints on the progenitors of type Ia supernovae. Here we have calculated the evolution of close binaries consisting of a white dwarf and a main-sequence or subgiant companion. We assume that, once Roche lobe overflow occurs a small fraction of the lost mass from the system forms a circumbinary disk, which extracts the orbital angular momentum from the system through tidal torques. Our calculations indicate that...

Source: http://arxiv.org/abs/astro-ph/0702218v1

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Sep 22, 2013
09/13

by
Denka Kutzarova; Denny Leung; Antonis Manoussakis; Wee Kee Tang

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In this paper, we study minimality properties of partly modified mixed Tsirelson spaces. A Banach space with a normalized basis (e_k) is said to be subsequentially minimal if for every normalized block basis (x_k) of (e_k), there is a further block (y_k) of (x_k) such that (y_k) is equivalent to a subsequence of (e_k). Sufficient conditions are given for a partly modified mixed Tsirelson space to be subsequentially minimal and connections with Bourgain's \ell^{1}-index are established. It is...

Source: http://arxiv.org/abs/math/0702210v1

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Sep 20, 2013
09/13

by
Tammy L. Bosler; Tammy A. Smecker-Hane; Peter B. Stetson

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We have obtained spectra of 102 red giant branch (RGB) stars in the Leo I dwarf spheroidal galaxy (dSph) and 74 RGB stars in the Leo II dSph using LRIS on the Keck I 10-meter Telescope. We report on the calcium abundances [Ca/H] derived from the strengths of the Ca II triplet absorption lines at 8498, 8542, 8662 angstroms in the stellar spectra using a new Ca II triplet calibration to [Ca/H]. The two galaxies have different average [Ca/H] values of -1.34 +/- 0.02 for Leo I and -1.65 +/- 0.02...

Source: http://arxiv.org/abs/astro-ph/0608197v2

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Sep 20, 2013
09/13

by
K. Yoshimi; M. Nakamura; H. Mori

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We study theoretically competition between the charge ordering and the superconductivity in two-dimensional organic conductor beta-(meso-DMBEDT-TTF)_2PF_6. We analyze the extended Hubbard model on a weakly-dimerized lattice based on the random phase approximation and Eliashberg equations. We found reentrant behavior of the checkerbord-type charge-ordered phase in the phase diagram, and the triplet superconductivity due to the charge fluctuation in the neighboring region. In the low temperature...

Source: http://arxiv.org/abs/cond-mat/0608466v3

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Sep 18, 2013
09/13

by
V. V. Kiselev

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For evolution of flat universe, we classify late time and future attractors with scaling behavior of scalar field quintessence in the case of potential, which, at definite values of its parameters and initial data, corresponds to exact scaling in the presence of cosmological constant.

Source: http://arxiv.org/abs/gr-qc/0611064v3

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Sep 22, 2013
09/13

by
François Caron; Manuel Davy; Arnaud Doucet; Emmanuel Duflos; Philippe Vanheeghe

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Using Kalman techniques, it is possible to perform optimal estimation in linear Gaussian state-space models. We address here the case where the noise probability density functions are of unknown functional form. A flexible Bayesian nonparametric noise model based on Dirichlet process mixtures is introduced. Efficient Markov chain Monte Carlo and Sequential Monte Carlo methods are then developed to perform optimal batch and sequential estimation in such contexts. The algorithms are applied to...

Source: http://arxiv.org/abs/math/0702225v1

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Sep 19, 2013
09/13

by
A. Bassi

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We review the major achievements of the dynamical reduction program, showing why and how it provides a unified, consistent description of physical phenomena, from the microscopic quantum domain to the macroscopic classical one. We discuss the difficulties in generalizing the existing models in order to comprise also relativistic quantum field theories. We point out possible future lines of research, ranging from mathematical physics to phenomenology.

Source: http://arxiv.org/abs/quant-ph/0701014v2

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Sep 19, 2013
09/13

by
A. M. Moro; M. Rodriguez-Gallardo; R. Crespo; I. J. Thompson

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Benchmark calculations are performed aiming to test the use of two different pseudo-state bases on the the Multiple Scattering expansion of the total Transition amplitude (MST) scattering framework. Calculated differential cross sections for p-6He inelastic scattering at 717 MeV/u show a good agreement between the observables calculated in the two bases. This result gives extra confidence on the pseudo-state representation of continuum states to describe inelastic/breakup scattering.

Source: http://arxiv.org/abs/nucl-th/0610059v2

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Jul 20, 2013
07/13

by
Takamasa Chiba; Tatsunori Imai; Hideki Asada

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None of N-body gravitating systems have been considered to emit periodic gravitational waves because of their chaotic orbits when N=3 (or more). We employ a figure-eight orbit as a specific model for a 3-body system in order to illustrate that some of triple stars are capable of generating periodic waves. This illustration would imply that a certain class of N-body gravitating systems may be relevant to the gravitational waves generation. We show also that the total angular momentum of this...

Source: http://arxiv.org/abs/astro-ph/0609773v4

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Sep 22, 2013
09/13

by
Y. Tsue; H. Fujii; Y. Hashimoto

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We investigate the chiral phase transition of a QCD-like theory, based the shape change of the effective potential near the critical point. The potential is constructed with the auxiliary field method, and a source term coupled to the field is introduced in order to compute the potential shape numerically. We also generalize the potential so as to have two independent order parameters, the quark scalar density and the number density. We find a tri-critical point locating at (T,mu)=(97, 203)...

Source: http://arxiv.org/abs/hep-ph/0702082v1

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Sep 22, 2013
09/13

by
Yun-Song Piao

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Recently, it has been shown in Ref.[1] that the string thermodynamic fluctuation may lead to a scale invariant spectrum of scalar metric perturbation. However, its realization is still in study. In this note we suppose that the correlation length of metric perturbation, which is proportional to the sound speed, might be nearly divergent at the critical point of phase transition. In this case we find that the string gas mechanism responsible for the generation of primordial perturbation may be...

Source: http://arxiv.org/abs/gr-qc/0702012v2

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Sep 22, 2013
09/13

by
Lu Yang; Shekhar Garde

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Partitioning and transport of water and small solutes into and through nanopores is important to a variety of chemical and biological processes and applications. Here we study the partitioning of positive ions of increasing size into the pore interior using extensive molecular dynamics simulations. Despite the simplicity of the simulation system, the results provide new and useful insights on both the pore hydration and ion partitioning. For low negative charge densities on the pore, the...

Source: http://arxiv.org/abs/physics/0702065v1

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Sep 22, 2013
09/13

by
Shay M Rappaport; Yitzhak Rabin

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We analyze several continuum models of polymers: worm-like chains, ribbons and Fourier knots. We show that the torsion of worm-like chains diverges and conclude that such chains can not be described by the Frenet-Serret (FS) equation of space curves. While the same holds for ribbons as well, their rate of twist is finite and, therefore, they can be described by the generalized FS equation of stripes. Finally, Fourier knots have finite curvature and torsion and, therefore, are sufficiently...

Source: http://arxiv.org/abs/cond-mat/0702203v1

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Sep 19, 2013
09/13

by
Hai-Jun Yang; Byron P. Roe; Ji Zhu

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In this paper, we compare the performance, stability and robustness of Artificial Neural Networks (ANN) and Boosted Decision Trees (BDT) using MiniBooNE Monte Carlo samples. These methods attempt to classify events given a number of identification variables. The BDT algorithm has been discussed by us in previous publications. Testing is done in this paper by smearing and shifting the input variables of testing samples. Based on these studies, BDT has better particle identification performance...

Source: http://arxiv.org/abs/physics/0610276v2

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Sep 22, 2013
09/13

by
Hamadi Abidi; Taoufik Hmidi

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We prove the global well-posedness of the critical dissipative quasi-geostrophic equation for large initial data belonging to the critical Besov space $\dot B^0_{\infty,1}(\RR^2).$

Source: http://arxiv.org/abs/math/0702215v1

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Sep 18, 2013
09/13

by
J-M. L. Beaujour; W. Chen; K. Krycka; C-C. Kao; J. Z. Sun; A. D. Kent

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We report on room temperature ferromagnetic resonance (FMR) studies of [$t$ Co$|2t$ Ni]$\times$N sputtered films, where $0.1 \leq t \leq 0.6$ nm. Two series of films were investigated: films with same number of Co$|$Ni bilayer repeats (N=12), and samples in which the overall magnetic layer thickness is kept constant at 3.6 nm (N=1.2/$t$). The FMR measurements were conducted with a high frequency broadband coplanar waveguide up to 50 GHz using a flip-chip method. The resonance field and the full...

Source: http://arxiv.org/abs/cond-mat/0611027v2

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Sep 20, 2013
09/13

by
CDF Collaboration

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A search for a manifestly exotic S=-2 baryon state decaying to Xi- pi-, and its neutral partner decaying to Xi- pi+, has been performed using 220 pb^(-1) of pp= collisions at sqrt(s)=1.96 TeV collected by the Collider Detector at Fermilab. The Xi trajectories were measured in a silicon tracker before their decay, resulting in a sample with low background and excellent position resolution. No evidence was found for S=-2 pentaquark candidates in the invariant mass range of 1600--2100 MeV/c^2...

Source: http://arxiv.org/abs/hep-ex/0612066v3

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Sep 22, 2013
09/13

by
Ken Wakita; Toshiyuki Tsurumi

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Community analysis algorithm proposed by Clauset, Newman, and Moore (CNM algorithm) finds community structure in social networks. Unfortunately, CNM algorithm does not scale well and its use is practically limited to networks whose sizes are up to 500,000 nodes. The paper identifies that this inefficiency is caused from merging communities in unbalanced manner. The paper introduces three kinds of metrics (consolidation ratio) to control the process of community analysis trying to balance the...

Source: http://arxiv.org/abs/cs/0702048v1

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Sep 22, 2013
09/13

by
Denis Gouvêa Ladeira; Jafferson Kamphorst Leal da Silva

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The chaotic sea below the lowest energy spanning curve of the complete Fermi-Ulam model (FUM) is numerically investigated when the amplitude of oscillation 'epsilon' of the moving wall is small. We use scaling analysis near the integrable to non-integrable transition to describe the average energy as function of time t and as function of iteration (or collision) number n. If t is employed as independent variable, the exponents related to the energy scaling properties of the FUM are different...

Source: http://arxiv.org/abs/nlin/0702018v1

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Sep 22, 2013
09/13

by
Herve Fabbro

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We describe the complex of solutions of the algebraic Mellin transform of a $\mathcal{D}$-module $\mathcal{M}$ in terms of the solutions of $\mathcal{M}$. In order to do that, we define a Mellin functor on sheaves. We show the Mellin transform of the complex of rapid decay solutions of a regular holonomic $\mathcal{D}$-module $\mathcal{M}$ is quasi-isomorphic to the complex of solutions of the algebraic Mellin transform of $\mathcal{M}$, the assumption of regularity not being necessary in the...

Source: http://arxiv.org/abs/math/0702229v1

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Sep 22, 2013
09/13

by
Hosho Katsura; Takaaki Hirano; Yasuhiro Hatsugai

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We investigate the entanglement properties of the valence-bond-solid states with generic integer-spin $S$. Using the Schwinger boson representation of the valence-bond-solid states, the entanglement entropy, the von Neumann entropy of a subsystem, is obtained exactly and its relationship with the usual correlation function is clarified. The saturation value of the entanglement entropy, $2 \log_2 (S+1)$, is derived explicitly and is interpreted in terms of the edge-state picture. The validity of...

Source: http://arxiv.org/abs/cond-mat/0702196v1

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Sep 22, 2013
09/13

by
Mark A. Taylor; Beth A. Wingate; Len P. Bos

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We present several new quadrature formulas in the triangle for exact integration of polynomials. The points were computed numerically with a cardinal function algorithm which imposes that the number of quadrature points $N$ be equal to the dimension of a lower dimensional polynomial space. Quadrature forumulas are presented for up to degree $d=25$, all which have positive weights and contain no points outside the triangle. Seven of these quadrature formulas improve on previously known results.

Source: http://arxiv.org/abs/math/0501496v2

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Sep 20, 2013
09/13

by
A. Maselli; S. Gallerani; A. Ferrara; T. R. Choudhury

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We investigate the possibility of constraining the ionization state of the intergalactic medium (IGM) close to the end of reionization (z ~ 6) by measuring the size of the HII regions in high-z quasars spectra. We perform a combination of multiphase smoothed particle hydrodynamics (SPH) and 3D radiative transfer (RT) simulations to reliably predict the properties of typical high-z quasar HII regions, embedded in a partly neutral IGM (x_HI=0.1). In this work we assume a fixed configuration for...

Source: http://arxiv.org/abs/astro-ph/0608209v2

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Jul 20, 2013
07/13

by
Götz S. Uhrig

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A general strategy to maintain the coherence of a quantum bit is proposed. The analytical result is derived rigorously including all memory and back-action effects. It is based on an optimized $\pi$-pulse sequence for dynamic decoupling extending the Carr-Purcell-Meiboom-Gill (CPMG) cycle. The optimized sequence is very efficient, in particular for strong couplings to the environment.

Source: http://arxiv.org/abs/quant-ph/0609203v2

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Sep 19, 2013
09/13

by
A. Mangiarotti; M. I. Lopes; M. L. Benabderrahmane; V. Chepel; A. Lindote; J. Pinto da Cunha; P. Sona

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The original Lindhard-Scharff-Schi{\o}tt (LSS) theory and the more recent Tilinin theory for calculating the nuclear and electronic stopping powers of slow heavy ions are compared with predictions from the SRIM code by Ziegler. While little discrepancies are present for the nuclear contribution to the energy loss, large differences are found in the electronic one. When full ion recoil cascade simulations are tested against the elastic neutron scattering data available in the literature, it can...

Source: http://arxiv.org/abs/physics/0610286v2

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Sep 22, 2013
09/13

by
Ed Troyan

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The velocity translation law for the patterns in the game of 'Life' is discovered. It is found for an arbitrary angle between the velocities in the moving reference frames. The formula differs from its physical prototype of special relativity but admits gentle reduction to the Galilean limit and provides absence of extra-light speeds.

Source: http://arxiv.org/abs/math/0702213v1

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Sep 22, 2013
09/13

by
M. Sharif

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Perfect-fluid, static, cylindrically symmetric solutions of Einstein's field equations are obtained for the equations of state $\rho+3p=0$ and $\rho=p$. In the former case, the density and the pressure turn out to be constant while in the later case, they depend on the radial parameter $r$. Evan's solution corresponding to the equation of state $\rho=p$ is included in the solutions discussed here.

Source: http://arxiv.org/abs/gr-qc/0702045v1

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Sep 18, 2013
09/13

by
J. D. Fletcher; A. Carrington; P. Diener; P. Rodiere; J. P. Brison; R. Prozorov; T. Olheiser; R. W. Giannetta

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We report measurements of the temperature dependence of both in-plane and out-of-plane penetration depths ($\lambda_a$ and $\lambda_c$ respectively) in 2\textit{H}-NbSe$_2$. Measurements were made with a radio-frequency tunnel diode oscillator circuit at temperatures down to 100 mK. Analysis of the anisotropic superfluid density shows that a reduced energy gap is located on one or more of the quasi-two-dimensional Nb Fermi surface sheets rather than on the Se sheet, in contrast to some previous...

Source: http://arxiv.org/abs/cond-mat/0605059v2

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Sep 22, 2013
09/13

by
R. H. France III; E. L. Wilds; J. E. McDonald; M. Gai

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We measured the beta-delayed alpha-particle emission spectrum of 16N with a sensitivity for beta-decay branching ratios of the order of 10-10. The 16N nuclei were produced using the d(15N,16N)p reaction with 70 MeV 15N beams and a deuterium gas target 7.5 cm long at a pressure of 1250 torr. The 16N nuclei were collected (over 10 s) using a thin aluminum foil with an areal density of 180 mu g/cm2 tilted at 7 Deg with respect to the beam. The activity was transferred to the counting area by means...

Source: http://arxiv.org/abs/nucl-ex/0702018v1

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Sep 22, 2013
09/13

by
Peter Steinberg

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The experimental and theoretical status of the ``near perfect fluid'' at RHIC is discussed. While the hydrodynamic paradigm for understanding collisions at RHIC is well-established, there remain many important open questions to address in order to understand its relevance and scope. It is also a crucial issue to understand how the early equilibration is achieved, requiring insight into the active degrees of freedom at early times.

Source: http://arxiv.org/abs/nucl-ex/0702020v1

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Sep 22, 2013
09/13

by
C. W. J. Beenakker

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Carl Gustav Hempel (1905-1997) formulated the dilemma that carries his name in an attempt to determine the boundaries of physics. Where does physics go over into metaphysics? The purpose of this contribution is to indicate how a recently developed field of research, the physics of computation, might offer a new answer to that old question: The boundary between physics and metaphysics is the boundary between what can and what cannot be computed in the age of the universe.

Source: http://arxiv.org/abs/physics/0702072v1

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Sep 22, 2013
09/13

by
Keiichi Ohnaka; T. Driebe; G. Weigelt; M. Wittkowski

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We present the first multi-epoch N-band spectro-interferometric observations of the carbon-rich Mira variable V Oph using MIDI at the ESO's Very Large Telescope Interferometer. Our MIDI observations were carried out at three different phases 0.18, 0.49, and 0.65, using three different baselines configurations (UT2-UT4, UT1-UT4, and UT2-UT3) with projected baseline lengths of 42-124 m. The wavelength dependence of the uniform-disk diameters obtained at all epochs is characterized by a roughly...

Source: http://arxiv.org/abs/astro-ph/0702226v1

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Sep 22, 2013
09/13

by
Rainer J. Fries

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We solve the Yang-Mills equations in the framework of the McLerran-Venugopalan model for small times tau after a collision of two nuclei. An analytic expansion around tau=0 leads to explicit results for the field strength and the energy momentum tensor of the gluon field at early times. We then discuss constraints for the energy density, pressure and flow of the plasma phase that emerges after thermalization of the gluon field.

Source: http://arxiv.org/abs/nucl-th/0702026v1

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Sep 22, 2013
09/13

by
Klaus Niederkrüger; Otto van Koert

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Recently Francisco Presas Mata constructed the first examples of closed contact manifolds of dimension larger than 3 that contain a plastikstufe, and hence are non-fillable. Using contact surgery on his examples we create on every sphere S^{2n-1}, n>1, an exotic contact structure \xi_- that also contains a plastikstufe. As a consequence, every closed contact manifold M (except S^1) can be converted into a contact manifold that is not (semi-positively) fillable by taking the connected sum of...

Source: http://arxiv.org/abs/math/0702228v1

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Sep 22, 2013
09/13

by
V. V. Kiselev

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In the framework of simple assumption on factorizing a mixing of vector state with isoscalar components in effective amplitudes of isospin breaking caused by the electromagnetic quark current, a branching fraction of radiative $J/\psi\to a_0$ transition is evaluated at the level of $3\cdot 10^{-3}$.

Source: http://arxiv.org/abs/hep-ph/0702062v2

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Sep 22, 2013
09/13

by
Emmanuel Wagner

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In analogy with a recursive formula for the HOMFLY-PT polynomial of links given by Jaeger, we give a recursive formula for the graph polynomial introduced by Kauffman and Vogel. We show how this formula extends to the Khovanov-Rozansky graph homology.

Source: http://arxiv.org/abs/math/0702230v1

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Sep 19, 2013
09/13

by
Jianguo Cao

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In this paper, we study certain compact 4-manifolds with non-negative sectional curvature $K$. If $s$ is the scalar curvature and $W_+$ is the self-dual part of Weyl tensor, then it will be shown that there is no metric $g$ on $S^2 \times S^2$ with both (i) $K > 0$ and (ii) $ {1/6} s - W_+ \ge 0$. We also investigate other aspects of 4-manifolds with non-negative sectional curvature. One of our results implies a theorem of Hamilton: ``If a simply-connected, closed 4-manifold $M^4$ admits a...

Source: http://arxiv.org/abs/math/0701742v2

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Sep 22, 2013
09/13

by
Ruben Garcia-Benito; Enrique Perez; Angeles I. Diaz

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We present results about the star formation process in the giant HII region NGC 5471 in the outskirts of M101. From resolved HST/WPFC2 photometry we find that star formation has been going for the last 70 Myr. We further compare previous results from integrated infrared-optical photometry with the stellar resolved CMD and we discuss the star formation properties of this region and its individual knots, as well as characterizing the different stellar content. This result has very important...

Source: http://arxiv.org/abs/astro-ph/0702238v1

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Sep 18, 2013
09/13

by
Wei Liao

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It is shown that the anomaly inflow mechanism can be implemented using Wilson line in odd dimensional gauge theories. An action of Wess-Zumino-Witten (WZW) type can be constructed using Wilson line. The action is understood in the odd dimensional bulk space-time rather than in the even dimensional boundary. This action is not gauge invariant. It gives anomalous gauge variations of the consistent form on boundary space-times. So it can be used to cancel the quantum anomalies localized on...

Source: http://arxiv.org/abs/hep-th/0605134v2

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Sep 22, 2013
09/13

by
A. Bürger

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In nuclear physics experiments involving in-flight fragmentation of ions, usually a large number of different nuclei is produced and various detection systems are employed to identify the species event by event, e.g. by measuring their specific energy loss and time-of-flight. For such cases -- not necessarily limited to nuclear physics -- where subsets of a large dataset can be identified using a small number of measured signals a software for fast access to varying subsets of such a dataset...

Source: http://arxiv.org/abs/nucl-ex/0702017v1

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Sep 18, 2013
09/13

by
Mariano Chernicoff; Alberto Guijosa

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We consider different types of external color sources that move through a strongly-coupled thermal N=4 super-Yang-Mills plasma, and calculate, via the AdS/CFT correspondence, the dissipative force (or equivalently, the rate of energy loss) they experience. A bound state of k quarks in the totally antisymmetric representation is found to feel a force with a nontrivial k-dependence. Our result for k=1 (or k=N-1) agrees at large N with the one obtained recently by Herzog et al. and Gubser, but...

Source: http://arxiv.org/abs/hep-th/0611155v3

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Sep 22, 2013
09/13

by
D. O. Gough

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Asymptotic expansion of the second-order linear ordinary differential equation Psi'' + k^2 f(z) Psi = 0, in which the real constant k is large and f = O(1), can be carried out in the manner of Liouville and Green provided f does not vanish. If f does vanish, however, at z_0 say, then Liouville-Green expansions can be carried out either side of the turning point z = z_0, but it is then necessary to ascertain how to connect them. This was first accomplished by Jeffreys, by a comparison of the...

Source: http://arxiv.org/abs/astro-ph/0702201v2

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Sep 22, 2013
09/13

by
Leonardo Giusti

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Algorithmic and technical progress achieved over the last few years makes QCD simulations with light dynamical quarks much faster than before. As a result lattices with pions as light as 250--300 MeV can be simulated with the present generation of computers. I review recent conceptual and numerical progress in this field, with particular emphasis on results obtained and difficulties encountered in simulations with significantly smaller quark masses with respect to previous computations. I also...

Source: http://arxiv.org/abs/hep-lat/0702014v1

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Sep 22, 2013
09/13

by
Thomas Strohmer; Roman Vershynin

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The Kaczmarz method for solving linear systems of equations is an iterative algorithm that has found many applications ranging from computer tomography to digital signal processing. Despite the popularity of this method, useful theoretical estimates for its rate of convergence are still scarce. We introduce a randomized version of the Kaczmarz method for consistent, overdetermined linear systems and we prove that it converges with expected exponential rate. Furthermore, this is the first solver...

Source: http://arxiv.org/abs/math/0702226v1

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Sep 22, 2013
09/13

by
Oliver Riordan; Mark Walters

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We use the method of Balister, Bollobas and Walters to give rigorous 99.9999% confidence intervals for the critical probabilities for site and bond percolation on the 11 Archimedean lattices. In our computer calculations, the emphasis is on simplicity and ease of verification, rather than obtaining the best possible results. Nevertheless, we obtain intervals of width at most 0.0005 in all cases.

Source: http://arxiv.org/abs/math/0702232v1

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Sep 22, 2013
09/13

by
N. Michel; W. Nazarewicz; M. Ploszajczak

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In the threshold region, the cross section and the associated overlap integral obey the Wigner threshold law that results in the Wigner-cusp phenomenon. Due to flux conservation, a cusp anomaly in one channel manifests itself in other open channels, even if their respective thresholds appear at a different energy. The shape of a threshold cusp depends on the orbital angular momentum of a scattered particle; hence, studies of Wigner anomalies in weakly bound nuclei with several low-lying...

Source: http://arxiv.org/abs/nucl-th/0702021v2

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Sep 20, 2013
09/13

by
Frantz Martinache; James P. Lloyd; Michael J. Ireland; Ryan S. Yamada; Peter G. Tuthill

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We have used Aperture Masking Interferometry and Adaptive Optics (AO) at the Palomar 200'' to obtain precise mass measurements of the binary M dwarf GJ 623. AO observations spread over 3 years combined with a decade of radial velocity measurements constrain all orbital parameters of the GJ 623 binary system accurately enough to critically challenge the models. The dynamical masses measured are $m_{1}=0.371\pm0.015 M_{\sun}$ (4%) and $m_{2}=0.115\pm0.0023 M_{\sun}$ (2%) for the primary and the...

Source: http://arxiv.org/abs/astro-ph/0612138v2

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32

Sep 22, 2013
09/13

by
Peter Steinberg

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The systematics of bulk entropy production in experimental data on A+A, p+p and e+e- interactions at high energies and large mu_B is discussed. It is proposed that scenarios with very early thermalization, such as Landau's hydrodynamical model, capture several essential features of the experimental results. It is also pointed out that the dynamics of systems which reach the hydrodynamic regime give similar multiplicities and angular distributions as those calculated in weak-coupling...

Source: http://arxiv.org/abs/nucl-ex/0702019v1

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35

Sep 22, 2013
09/13

by
F. de Melo; S. P. Walborn; János A. Bergou; L. Davidovich

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We present a quantum circuit that implements a non-demolition measurement of complementary single- and bi-partite properties of a two-qubit system: entanglement and single-partite visibility and predictability. The system must be in a pure state with real coefficients in the computational basis, which allows a direct operational interpretation of those properties. The circuit can be realized in many systems of interest to quantum information.

Source: http://arxiv.org/abs/quant-ph/0702079v1

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Sep 22, 2013
09/13

by
Limor Ben-Efraim; Francoise Lust-Piquard

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We prove Lp Poincare inequalities for functions on the discrete cube and their discrete gradient. We thus recover an exponential inequality and the concentration phenomenon for the uniform probability on the cube first obtained by Bobkov and Gotze. Inequalities involving the discrete gradient and powers of the discrete Laplacian are also considered, for the Lp norm or more general ones. Similar results hold true, replacing functions on the cube by elements of the CAR algebra and considering the...

Source: http://arxiv.org/abs/math/0702233v1